Thread tension arrangement for knitting machines



Nov. 24, 1953 $HM|DT 2,660,041

THREAD TENSION ARRANGEMENT FOR KNITTING MACHINES Filed Dec. 22, 1950 2Sheets-Sheet 1 Fl E- l Z2 INVENTOR BY FauLS hmidi 6 p fozw TTORNEY Nov.24, 1953 P. SCHMIDT 2,660,041

THREAD TENSION ARRANGEMENT FOR KNITTING MACHINES Filed Dec. 22, 1950 2Sheets-Sheet 2 INVENTOR PauZSchmidi BY Moan;

ATTO R N EY Patented Nov. 24, 1953 THREAD TENSION ARRANGEMENT FORKNITTING MACHINES Paul Schmidt, Wytheville, Val, assignor to TextileMachine Works, Wyomissing, Pa, a corporationof Pennsylvania ApplicationDecember 22, 1950, Serial No. 202,219

7 Claims. 1

Thepresent invention relates to yarn tension.-

ing means and more particularly to such means for maintaining the yarntaut to the needles of a full-fashioned knitting machine duringoperating periods of the needles in which no yarnis fed thereto.

through yarn carriers and to the needles of the mach ne, the tensioningdevices applying sufiicient tension on the yarn as it is fed to thesink.- ers of the machine by the carrier to form loops of the requiredsize. The yarn carrier is stopped at. the end of its yarn feedingmovement and remains stationary while the new loops are divided andknitted into the fabric. The yarn carrier also. remains stationaryduring narrowing cycles of; the machine and during such periods in whichthe yarn carrier isstationary, the snapper devices and. rings act to.take up and maintain the yarn taut between the rings and the needles so.as to'iiorm normal size loops at the outer selvage edges of the fabricknitted. However, when us.- iing'the finer denier yarns and particularlythe mono-filament nylon yarns, the rings instead of maintaining theyarns taut to the needles withdraw sufficient yarn from the supplypackages to. permit the rings to drop to a stop position :at. the. lowerend of the ring, supports. With this condition the rings no. longerfunction to take up \the slack as the needles go through their knit-Rfihg in and narrowing movements thereby re.- .sulting in abnormallyloose selvage loops and :ragged' selvage edges.

It is accordingly an object of the invent on to provide a means forovercoming the difficulty .hereinbefore set forth.

'Iti's another object of the invention to provide 'Ineans applying adrag to the yarn between the yarnsupply and the usual tensioning ringwhere. by the ring will function normally to take-up the slack in andmaintain the yarn taut between the ring and the needles.

' Still another object of the invention isto provide a-simple andreadily replaceable means for maintaining tension on the yarn to theneedles whenthe yarn carrier is stationary;

With these and other objects in View, which will become apparentfrom thefollowing detailed description of the illustrative embodimentof theinvention shown in the accompanying drawings, the invention residesinthe novel elements, features of construction and arrangement of parts incooperative relationship as hereinafter more particularly pointed outinthe claims;

'In the drawings:

Figure 1 is Y a sectional elevation of a portion of a full"-fashioned kntting machine; having; theiifi; ifention: a plied thereto; W

from said tensmmngmean'swhrough anng whose Fig. 2 is a detail view of aportion of the mechanism of Fig. 1 and shown on an enlarged scalerelative thereto; 7

Fig- 3 is a detail view of a portion of the mechanism of Fig. 1 andshown on an enlarged scale relative thereto;

Fig. 4 is a view similar .to Fig. 3 showing further details of certainof the mechanism shown in Fig. ,1; v

Fig.5. is a. viewof the upper portionof Fig, '1 on an enlarged scalerelative thereto, parts being omitted for purposes of illustration; 1

Fig.6 is an elevational view of a portion or Fig. ,5 looking in thedirection of the arrows 6-6 of Fig. 5; i I a V Fig- 7. is a sectional.view taken substantially on the, line 'l.1 of Fig. 6; and

r Fig. 8 is a sectional view taken substantially on the l ne 8-8 of.Fig- 6.

In the drawings and description, onlytlie means necessary to a completeunderstanding of the inventionare specifically set forth; further Inor?- mation as to the construction and operation of other related...usual and well known knitting machine elements, mechanisms, etc., may"be found in one or more of the following publications:

vl. Pamphlet entitledFiill-Fashioned Knits ting Machines'-publishe'd andcopyrighted by the Textile Machine Works, Reading, Pennsylvania, in1920-. I, I 4 i 2], catalogs entitled-The Reading? Full-FashionedKnitting. Machine Pampers: log-published and copyrighted by the TextileMachine Works, in 1929,1935; 1940 and 1947, re spectively. I I I,

3. Booklet entitledl The Reading High Production Full-Fashioned KnittingMachine which, forming a supplement to theabove noted 1940 Parts Catalogof' the Textile Machine Works, is a publication of the Textile MachineWorks, copyrighted by the latter in 1940'.

4'. Pamphlet entitled-Knitting Machine Lee turespublishedi by theWyomissing Polytechnic Institute; Wyomissing, Pennsylvania, in 1935;

In a; machine" having the invention applied thereto; a: usualyarncarrier is employed? for laying yarn to the needles and the yarnsupply for'the carrier is in the form of a coneor" other convenientpackage in ayarn box fromwhich the yarn passes over a guide rod" andthence either toand through a moist'ening trough, ifthe yarn is to bemoistened before being knitted or" above the moistening troughif it isnot to bemoistened. Certain tensioning means are usually provided in themoisteni'n'g trough for yarn passing" there through and tensionirig'means a comparable location is provided also for" yarnby passing themoiste'ning' box-1 In either case"; the'yarn passes forwardli'orizontally toward the yarn carrier needles.

3. weight is supported by the yarn at least as long as yarn is beingdrawn by the yarn carrier. From the ring the yarn passes also generallyhorizontally forward through a pair of guide eyes in an oscillatorysnapper device and then downwardly through fixed guide means to the yarncarrier the various elements through and over which the yarn passesproviding a predetermined tension in the yarn at the time it is fed orlaid to the needles to form the required size loops. With thisarrangement, the normal function of the ring is to take up the slack inthe yarn between the moistening trough and the needles when the carriercomes to a stop between yarn feeding strokes and during narrowing cyclesof the machine. However, in many instances, and particularly where thefiner gauge mono-filament nylon yarns are used, the tension in the yarnbetween the ring and the yarn supply is less than the tension in theyarn between the ring and the Under these conditions the ring, insteadof taking up the slack in the yarn to the needles, withdraws sufiicientyarn from the yarn supply to permit the ring to drop to a fixed positionat the lower end of the ring support where- .bythe normal function ofthe ring is lost. In

accordance with the invention, this difficulty is avoided by providing ameans adapted under certain circumstances to tension the yarn at a pointbetween said tension ring and the yarn package and under othercircumstances to be inactive or inoperative as to applying tension tothe yarn. Said last means is arranged so that it does not applyadditional tension to the yarn when the yarn carrier is laying yarn tothe needles but will act to increase the drag on the yarn only when thecarrier is stationary and the ring has caused the yarn to sag from itshighest position.

Referring to the drawings in detail, there is shown in Fig. 1 a needleIU of a row of needles held on a needle bar l2 of a full-fashionedknitting machine. Sinkers l4 and dividers l5, cooperate with the needlesin forming loops of knitted fabric by pushing yarn between the stems ofthe needles in the usual manner. The yarn or "yarns on which thesinkers, dividers and needles operate is or are laid by means of a yarncarrier or yarn carriers [6 of which each fullfashioned machine may haveas many as nine per knitting section and which are reciprocated in apath parallel to the needle row. Yarn is supplied to each yarn carrierfrom a yarn package such as one of cones I8 mounted in a yarn box suchas 20. From each of the cones l8 or other suitable yarn packages a yarn22 passes upward around one of rods 24 and thence forward throu heyelets 26 or 28 best shown in Fig. 5. Eyelets 26 guide certain of theyarns 22 to tensioning and moistening means of known form inside amoistening box or trough 30 while eyelets 2') guide others of the yarns22 beneath tensioning plates one of which is shown at 32. From thetensioning means in box 30 and the one comprising plate 32, the yarnspass respectively through guide eyelets 34 and 36 and thence throughtensioning rings 38 and 40 respectively. These rings are guided to movein vertical lines on supports 39, mounted in fixed position on a member31 carried on the machine frame. Each support 39 is provided with aportion 4| forming a stop for a ring when no yarn passes through thering or when the carrier for the yarn is idle and no tension required onthe yarn. The yarns pass from the rings through guide eyelets 3?. and 35in arms 42 and 44 respectively of snapper devices 43 and 45,respectively, mounted on oscillatory shafts 46 and 48, respectively.From the eyelets 33 and 35 in arms 42 and 44, the yarns pass to eyelets50 and 52 in arms 54 and 56 respectively which also form parts of thesnapper devices 43 and 45 on shafts 46 and 48. The eyelets 50 and. 52are set to cause the yarn to turn from a substantially horizontalposition to a substantially vertical position. From eyelets 50 and 52the yarns pass downwardly through guide meanssuch as eyelets 58 and overrods 60 and thenceto the yarn carriers [6.

As shown in Fig. 1, means for oscillating shafts 46 and 48 and therebythe snapper arms thereon;- comprises cams 6| and 62 on a main cam shaft64 of the machine, cam 6| acting during knitting cycles and cam 62acting during narrowing cycles of the machine. A cam follower 66 ismounted for rotation at one end of a lever 68 pivotally mounted at 10 onthe frame of the machine, the other end of lever 68 having a tensionspring 12 attached thereto so as to hold the cam follower 66 in contactwith the cams 6| or 62. Near its point of attachment to spring 12, lever68 is pivotally connected to a link 14 which is pivotally connected to alever arm I6 which is fixed to shaft 48, as shown in Fig. 3, whereby theend of arm 16 is lifted each time cam 6| or 62 presents a high spot tofollower 66 and shaft 48 thereby is turned in a clockwise direction asviewed in Figs. 1 and 5. Spring 12 causes shaft 48 to turncounterclockwise as follower 66 moves from a high to a low spot on thecams. In order that shaft 46 may be turned correspondingly to shaft 4 8,shaft 48 has a second lever arm thereon shown at 18. Arm I8 is shown inFig. 4 as connected to a lever arm by a link 82, arm 80 being fixed toshaft 46 so that shafts 46 and 48 turn together.

In accordance with the invention, devices 86 and 88 are provided, device86 cooperating with the yarns 22 passing through the moistening trough30 and device 88 cooperating with the yarns 22 passing beneath thetension plates 32, as hereinafter set forth. Devices 86 and 88 comprisea felt strip or block carried in a receptacle 8! of substantiallyU-shape, as shown in Figs. 2, 5 and 6, the receptacles being supportedby bolts 96 on hangers 89. As shown in Fig. 5, one end of each hanger 89is carried on the member 31 and the other end thereof is formed to fitover and be supported on the shaft 46. The bolts 96 are slotted toreceive the hangers 89 and are adjustably secured to the hangers by nuts9|. The receptacles 81 are maintained in predetermined relation on thehangers 89 by wing projections 92 formed on the receptacles to fit overthe bolts 90, Figs. 6 and 8, and by projections 93 also formed on thereceptacles to fit around the hangers, as shown in Figs. 5 and '7. Withthis arrangement, the devices 86 and 88 may be readily adjusted on thehangers 89 to vary the drag applied to the yarns 22 and the receptacles8'! are readily removable to clean or replace the felts 85.

In operation, when a yarn carrier I6 is moving parallel to the row ofneedles H], the carrier draws the yarn 22 from its cone 18 withsufficient tension in the yarn, due to the drag provided by the plate 32or an equivalent means in the trough 36, to lift the ring 38 or 46 tothe position shown in Fig. 5 and in which the yarn extends in asubstantially straight line from the eyelet 34 or 36 to the eyelets 33and 35 in the arms 42 and 44 of the snapper devices 43 and 45,respectively. In this condition, the yarns freely pass above and out ofcontact with the felt strips 85 of the devices 86 and 88. However, whenthe carrier is stationary during the loop forming movement of theneedles the snapper devices 43 and 45 are turned in a counterclockwisedirection by the action of the cam 5| which gives a tug to the yarn toremove any slack in the yarn between the needles and the eyelets 50 and52 of the snapper devices, the rings 38 and 40 immediately dropping bygravity to take up the slack. As the rings 38 and 40 drop, the yarnportion extending between the ring 38 and the eyelet 34 in the trough isdrawn into engagement with the felt strip 85 of the device 86, as shownin Fig. 2, the felt strip acting as a brake resisting withdrawal of yarnfrom the yarn supply side of the ring, and the ring thereby acting tohold the yarn taut to the needles. The ring acts in like manner to drawthe yarn against the felt strip 85 of the device 88 thereby resistingwithdrawal of yarn from the supply side of the ring. The rings 38 and 48thereby function to maintain the yarn taut to the needles throughout theloop forming movement of the needles in each knitting cycle. Likewise,the rings 38 and 40 act to maintain the yarn taut to the needles duringnarrowing cycles of the machine, the rings being assisted by slighttugging movements of the snapper devices 43 and 45 through the action ofthe narrowing cam 82. Therefore, during both knitting and narrowingmovements of the needles in which the carriers 56 remain stationary, thefelt strips 85 resist withdrawal of the yarns from the yarn supplies andthereby permit the rings 38 and 40 to function in a normal manner totake up and maintain the yarn taut to the needles resulting in theformation of normal size selvage loops in the next knitted course.

Of course, the improvements specifically shown and described by which Iobtain the above results, can be changed and modified without departingfrom the invention herein disclosed and hereinafter claimed.

What I claim is:

1. In a full-fashioned knitting machine, means for supplying yarn, asnapper arm through an aperture in which the yarn passes to a yarncarrier, a tensioning ring through which the yarn but which contacts theyarn when the yarn ten sion slackens to cause the ring to maintain atension on the yarn at the delivery side of the yarn carrier.

2. In a full-fashioned knitting machine, means for tensioning yarnbetween a yarn supply and a yarn carrier comprising a freely floatingtensioning ring through which the yarn passes to said yarn carrier, ablock beneath the yarn on the far side of said ring from the carrier andcomposed of material adapted to place a drag on the yarn when in contacttherewith, and guide means for the yarn acting to hold it free of saidblock when under sufiicient tension to hold the ring at its highestlevel but permitting the yarn to sag at times against said block whensuch tension is relieved.

3. In combination with a yarn feeding system, a tensioning ring guidedfor free vertical motion and through which a yarn passes from a yarnsupply to a fabric being knitted, members one on each side of the lineof movement of said ring and forming guides through which yarn passes toand from said ring and a tensioning device between the vertical line ofmovement of said ring and the yarn supply, said ring being adapted todraw the yarn into contact with said tensioning device to produce dragon the yarn to cause a tension in the yarn equal to at least half of theweight of the ring.

4. In a knitting machine, a yarn tensioning means comprising a freelymovable tensioning ring guided for vertical movement and through which ayarn is threaded in use and a friction device arranged to be free of theyarn when the ring is in its topmost position but adjustable to aposition in which it contacts and places a drag on the yarn when theweight of the ring causes the yarn to sag.

5. In combination with a yarn feeding system for a knitting machine, atensioning device comprising a part having a high coeincient of frictionwith respect to the yarn, a bolt on which said part is supported and avertical wire-like support for said bolt, said bolt having a slot at itsthreaded end to receive said wire-like support, and a nut on said boltto clamp the wire-like support against the end of said slot.

6. In a knitting machine, in combination with a system for feeding yarnfrom a supply to the needles of the machine to form knitted loops, aring guided for free vertical movement through which the yarn passes,said ring being adapted to drop by gravity from a position controlled bythe yarn during feeding thereof to a position to takeup slack in theyarn, guide means for the yarn between the ring and supply, guide meansfor the yarn between the ring and needles, said guide means and ringapplying a predetermined tension to the yarn as it is fed to the needlesand means between the supply and ring normally out of engagement withthe yarn during feeding thereof to the needles and adapted to be engagedby the yarn when the ring drops in its take-up action to therebyincrease the tension on the yarn between said supply and ring.

'7. In a full-fashioned knitting machine, means for supplying yarn, atensioning ring guided for vertical movement, a yarn guide between saidyarn supply means and said ring, a second yarn guide between said ringand knitting instrumentalities of the machine, said yarn passing throughsaid first guide, said ring and said second guide and means having ahigh coefficient of friction with respect to the yarn supported betweensaid first mentioned yarn guide and said ring and below the straightline path between said guides to exert a drag on said yarn when saidyarn is drawn into contact therewith by downward movement of said ring.

PAUL SCHMIDT.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,046,293 German June 30, 1936 2,196,088 Vogler Apr. 2, 19402,281,427 Freer Apr. 28, 1942 2,373,854 Searles Apr. 17, 1945 2,514,582Johnson July 11, 1950 2,522,211 Crawford Sept. 12, 1950 2,539,953Hoffecker Jan. 30, 1951 2,566,005 Ward Aug. 28, 1951 2,566,006 Ward Au28 1051

